Friction clutch



Nov. 28, I933.

W. F. HUGHES FRICTION CLUTCH Filed Feb. 28, 1931 2 Sheets-Sheet l NOV. 28, 1933. w HUGHES I 1,937,083

FRICTION CLUTCH Filed Feb. 28, 1931 2 Sheets-Sheet 2 I I I I I I l Patented Nov. 2 s, 1933. 1 7' 1,937,083

UNITED- STATES PATENT,-oFFICEiI Rockford Drilling Machine (10., Rockford, Ill., a corporation'of Illinois Application February 23, 1931. Serial No "518,958 7 13 Claims. (014192-68) 1 This invention relates to friction clutches genofcourse, Wellknown, Myinvention is concerned; erally, and is particularly concerned with one with-novel details of construction and arrange? adapted for use on a motor vehicle. a ment in the various-portions ofthe clutch as The principalobject of my invention is to prohereinafter fully described. v vide a clutch made up largely of sheet metal a It hasv been common practice to make the pres 60 stampings with a view to cutting down machining sure plate of cast iron. 'That, however, necessi-' operations to a minimum, and accordingly lower tated expensive machining operations, and the in st, an l m f lightness d duraconstruction was also objectionable because of' bility. excessive weight and the fact that'uneven heat 10 Another Object is t0 provide a tch embody ing and cooling of the pressureplate meant .dis- 65 adjus ments of simpl r and he p r m r tortion; and cracks were frequently developed; t than v been Provided in the Past, necessitating replacements. According to; my ones which are so disposed that the adjustments invention, therefore, the pressure plate 14 is made can be made with greater ease and facility than in th form of a ringhaped sheet metal Stam s:

v 15 has otherwise been the case.- ing; made of fairly thick sheet metal, weighing' Other objects and advantages will appe in only afraction ofwhat'an ordinary cast plates the course-of the following description, in which would i h, Thus the driving face 13 is pro-- reference is made to the accompanyi drawings, vided without the necessity of any machining opwherein eration. While the plate is made of thick sheet Fi r 1- i a n r l loneitudiml'seption In a metal, its thickness is,' nevertheles's, about halo-,

, Vertical plane through. a Clutch mad-e accordv the thicknessof a cast plate; and inorder to make ance with my invention; V I the same rigid, I prefer to havev the inner mar 2 is a Sectional detail on ,2 f ginal portion struck so asto providean annular Figure 1, and e g v reinforcing rib V22; There-is; therefore,.litt1e':

F 3 is a r ie of Figure with certain likelihood of the plate g'ettingout of'shape. ."I 'o 80 portions b o away bECaU-SBOf the limited spate still further insure'ri'gidity of the pressure plate, available in the -r- I provide a backing therefor in the form of a Same TefeTen e1num3ra1S are i to stamped light sheet metal ring 23 preferably correSponding partsethlougheut Viewschannel-shaped in crossesectioni suitablywelded Referring to Figure 1, the li the englne tothe plate 14, as'indicated at24, by thetrough crank shaft appears t having the ii/ portion of the channel, leaving the flangesof the mount thereon in the y- A D lP bearchannel projecting rearwardly from the plate mg 111 the end of the Clank Shaft recelves e annularly of the marginal portion thereof-to pro; from? end of the driven shaft 8 which: extends vide the desired reinforcement. The composite rearwardly from the flywheel d clutch into he plate 'thus constructed still weighs much less 9 gearbox of h transmission in the usual W than the ordinarycast pressure plate and, due to The clutch d1sc 9 has its center hub 10 splined the Special formi th f is boundtokeep t 7 on the shaft 8, and pads or facings 11 are fastened shape is evident ,that the annular flange on opposite sides of the'rnarginal portion for enand the annular ribiwm i o y o r'eim 40 easem t on one slde Wlth the dill/mg face force the plate, but also radiate heat theref om back flywheel 1 whereby further to minimize likelihood of distorother side with the drlving face 13 providedon vThar; is, courSQ-m, danger whatever the front of the pressure plate 15 is the back of this pressure plate developing. cracks plate fastened as at 16 to the rim. of the flywheel heating, arid, coming in service; The tract and provided with a, series of holes 17 equally .r I 1 spaced circumferentially thereof in which pressed .stampmg W mf consldereible S n 0 in cost, since it IS ObVlOUS that there is no comsheet metal thimbles 18 are entered to serve as k y p cages for coiled compressionfsprings 19. The m e of h Weldmg Q 1Qp- 9 latter urge thepressure plate 14 toward the flymachining Operations t a w r q e 'w i wheel for engagement of the clutch. In the disa t platesuse of t backing 3 a o 50 engagement of the clutch, the pressure plate 14 is taken advantaged o. a e the inner nd 1 5' retracted against the action of the springs by the springs 19 by formingv hollow cone-shaped means of release levers 20 actuated by the throw bosses on the ring 23 in register with the holes out collar 21 which in turn is given movement by 17 ro de in the c plate 15 Q which t depression of the clutch pedal in the usual way. inner ends of he Sp s 931 arrene dt The arrangement thus far generally described, is, I also'use the ring'23, as ameansof anchoring a Y V scribed.

3 ,holes '32 provided in the back plate.

that no'additional costis involved in providing The back plate is also often made in the form of a casting, but in keeping with the spirit of my invention, I prefer to have the same also stamped from sheet metalfor lightness andcheapness. The desired rigidity is assured by fianging the inner edge, as appears at 29. Now, it will be observed that I have provided a plurality of notches in the annularly ribbed inner marginal portion 22 of the pressure plate 14. Lugs 31 are formed integral with the flange 29and project forwardly therefrom through the notches 30.

Thelugs', of which there are three to correspond to the three notches, althoughof course,'the particular' number used-is more or less immaterial, have a close working fit in the-notches to permit the pressure plate 14 to have free movement relative to the back plate toward and away from the flywheel in the engagement and disengagement of the clutch. The lugs, in other'words, make the pressure plate turn with the back plate and flywheel and relieve the studs 26 of the duty of making the pressure plate turn with the back plate, the said studs being passed freely through It is obvious this interlocking feature, inasmuch as the notches and the lugs forentry therein are formed when the pressure plate and back plate are stamped an formed, as above described; I

"Therelease levers 20;in keepingwith the spirit of the invention, are also-"stamped from sheet metalto a generallychannel-shaped cross-sec V tion'so as to provide spaced longitudinal flanges 3- on each of these levers joined by a web portion 34:, the inner endof which is formed substantially half around to provide a finger 35 for'engagernent with the front of thethroW-out collar 21. J A square post 36 which has a reduced shank por- ;.tion 3'1 riveted to theback plate15,'as indicated at 38, is provided in connection with each release lever and flts' between the flanges 33 near the outer; end of the lever, and accommodates a pivot pin'39 ina hole provided'in the post-in register with holes provided in the flanges 33. A cotter pin40'is provided on theprojecting. end of the. pin 39, as indicated in Fig; 3, to keep the parts in assembled relation. The holes in the flanges 33 for the pin 39 will be slightly elongated for a reason soon to appear. The web 34 terminates short of the outer endof the flanges and the latter project beyond the post ,36 between the ears 4l of a U-shaped yoke 42 suitably formed of sheet metal, Small studs 43 arepassedthrough; registering holes in the flanges 33 and ears 41- "from the inside of the fiangesso that the heads 44. on these studs abut the inside of the flanges,

whereuponthe projecting ends of the studs are upset, as indicated at 45, to permanentlylpivotally secure 'the parts together. The stud 26 in the case, ofneach of these release levers 20, of which there are three, one foreach stud, projects rearv,wardly from the backplatebetween'the outer ends of the flanges '33, and has its rear end threaded as at 46in a nut 47 rotatably mounted The studs 26 form a partof the clutch release mechanism hereinafter dein the web of the yoke'42 between the cars 41 thereof. The nut 47 is suitably provided with'a reduced shank portion 48 entered freely through a hole [provided in the web of the yoke 42 and has the end of said shank swedged outwardly as at 49 to permanently assemble the nut on the yoke with freedom to turn with respect thereto. The

nut is preferably castellated to permit fastening the same in adjusted position on the stud by means of a cotter pin 50. The loose fit of the nut inlthe yoke may be relied upon to compensate for the fact that the studs 43 have to travel in an are about the pin 39 as a center, the deviation from a straight line motion being so slight. However, it is-preferred to have the holes in the flanges 33 for the pin 39 slightly elongated so as to have the release lever free to move endwise a slight amount in its pivotal movement relative to the pin 39.

In operation, the nuts 47 are arranged to be adjusted so that when the clutch is engaged the release levers 20 will have the same clearance at their innerends 35 with respect to the throw? out collar 21.' This insures proper engagement and disengagement of the clutch in th'e fore and' aft movement of' the throw-out collar. After" the clutch has been in service for a time, any

unevenness in wear is readily compensatedfor by unscrewing one or more of the nuts 4'7 one or more turns than the rest. The cotter pins 50 prevent the clutch from losing its adjustment. It is evident that since the nuts 4'7 are fully exposed to the rear of thebackplate, they are easily accessible upon removal of the inspection plate on the housing, thus greatly, simplifying the matof making an adjustment of the clutch. The I swiveling of the'nuts and the arrangementfm"v locking the same with cotter pins instead of -rely- 1 ing upon lock nuts has been found to be far more practical and permit of more. accurate adjustment than previous forms of'adjustments. Here again, of course, the fact that most of the parts are made of sheet metal is of advantage from the standpoints of low cost and less weight. I claim:

element, and a driven element, a back. plate on the driving element, a"pres'sure plate, spring means acting between the back plate and the pressure plate to urge the latter in a direction for engagement of the clutch, means for retracting the pressure plate against the actionofi said spring means, the back plate being-provided with one or more lugs projecting forwardly'from the inner marginal edge thereof substantially at right angles to the planeof the back plate, and

said pressure platehaving one or more openings-' provided therein slidably receiving said lugs whereby the pressure plate is caused to turn pos itively with the driving element but is free 'to: move forwardly and rearwardly with respect to the-back plate in the engagement anddisengage-' ment of the clutch.

2. In a friction clutch comprising a driving: element, and a driven element, a back plate on vdriving elem a pressure plate, spring,-"

means acting between the back plate and the pressure plate to urge the latter in a direction for engagement of the clutch, means for retract; ing the pressure plate against the action of said spring means, the said back plate being stamped from a piece of sheet metal formed to provide one or more lugs projecting forwardly from the inner marginal edge thereof substantially at right- I angles to 'theplane of the back plate, and said 1. 'In a friction clutch comprising a driving 1.2%"

driving element, a pressure :plate, and spring means acting between the back plate and the pressure plate for normally urging the latter toward the driving element, means for retracting 'the'pressure plate against the action of the spring means comprising a stud projecting rearwardly from the pressure plate through a hole provided in the back plate, the same having the rear end thereof threaded, a nut threaded on the rear end of said studpa release lever pivotally mounted intermediate its ends on the back plate arranged to have pivotal movement communicated thereto at one'end, and having its other end reaching toward said stud, and a member pivotally connected to the latter end of said layer and having said nut mounted thereon to swivel with respect thereto whereby to permit plate for normally urging the latter toward the flywheel, means for retracting the pressure plate against the action of the spring means comprising a stud projecting rearwardly from the pressure plate through a hole provided in the back plate, the same having the rearend thereof threaded, a nut threaded on the rear end of said stud, 'a-release lever pivotally mounted intermediate its ends on the back plate and arranged to have pivotal movement communicated thereto'at one end and having the other end bifurcated-and straddlingthe projecting portion of said stud between the nut and the back plate, and a substantially U-shaped yoke member having said nut" swiveled on the cross portion thereof, and havjingthe two arms thereof pivotally connected to the bifurcated end of said lever, the swiveling of said nut on said yoke member permitting ad justment of the nut relative to the stud while maintaining a predetermined relation between a the nut and yoke member.

, from the pressure plate through a hole provided in the back plate, the same having the rear end thereof threaded, a nut threaded on the rear end of said stud, a stamped sheet metal release lever formed generally channel shaped in cross-section so as to provide a pair of longitudinal spaced side flanges joined by a web portion, a support for said lever extending from the back plate between the longitudinal flanges of the lever for pivotally mounting said lever intermediate its ends, the 7. 'said lever being arranged to have pivotal movenut to the yokemember;

ment communicated thereto at one end, the said longitudinal flanges providing a forked portion at the other end of said lever fitting about the projecting portion of the stud between 'the nut and the back plate,-and a stamped sheet metal U-shaped yoke member having the arms thereof'straddling the forked end of" said lever and pivoted thereto, said nut being swiveled onand projecting from the cross portion of saidyoke member-whereby to permit adjustment of the nut on the stud without changing the relation of the 6. In a friction .clutch ;comprising a driving element, and'a driveneleme'nt, a back plate,'a pressure plate, andsmeans for moving the pressure plate relative to the back plate" comprising a stud projecting rearwardly from the pressure plate through a hole provided in the back plate, the sameha'ving the rear end thereof threaded, a lever pivotally mounted intermediate its ends on the back plate and arranged to have'pivotal movement'communicated thereto at one end, the other end of said lever reaching'toward said stud, anda nut threaded on the rear end'of said stud 'and 'mounted on the last mentioned end of said 1M lever as to turn relative thereto but be held against endwise movement with respect thereto whereby to permit a change in the relationship of the nut to the stud 'while'maintaining substan-i tially the same relationship between the nut and the lever. r

'7. In a friction clutch comprising a driving element, and a driven element, a back plate, a'p'ressure plate, and means for moving the pressure plate relative'to the back plate comprising a stud projecting rearwardly from the pressure plate through a hole provided in the back plate, the same having the rear end thereof threade'dja lever p'ivotally'mounted intermediate its ends on the ,backplate and arranged to have "pivotal movement communicated thereto at one end and having theother end: bifurcated and straddling the projecting end of saidstud, a'yoke member pivotally connected to the bifurcated end of: the lever, and anut threading on the end of "said-l2?) stud and swiveled on th'e'yoke' member'whe'reby to permit adjustment of the nut relative 'to the w stud while maintaining a predetermined relation between the nut and the lever.

8. In a friction clutch comprising a driving element, and a driven element, 'a back plate, a pressure plate, and means-for moving the pres;- sure plate relative to the back plate comprising a stud projecting rearwardly from the pressure 7 plate through a hole provided in the backplate, 180

the same having the rear end thereof threaded,

a stamped sheet metal lever formed generally channel-shaped in cross-section so as to provide, f a pair of longitudinal spaced side flanges joined by a longitudinal web portion, a support for said lever extending from the-back plate and having the longitudinal flanges of "the lever pivotally mounted thereon intermediate the ends of said lever, said lever being .arrangedlto have pivotal movement communicated thereto at one end, the said longitudinal flanges providing a forked portion at the other-end of said lever straddling-the projecting end of the stud, astamped sheet metal U.-shaped yoke member having the arms thereof straddling the forked end of the lever and piv- M5 oted thereto, and a nut swiveled on thecross por'-, tion of the yoke member and threaded on the stud whereby to permit adjustment of the nut on the stud without changing the relation of the nut 1 to thelever. 156' ail 9. Ida clutch comprising" a driving element and a driven element, a back plate, a pressure plate mounted so as to turn with the driving element and the back plate, and means for moving the pressureplate relative to theback plate comprising a lever pivot-ally mounted intermediate its ends on a support projecting rearwardly from the back plate and arranged to have pivotal movement communicated thereto at one end, a link connection between the pressure plate and the other end'of said lever for communicating movement to the pressure plate from thelever, means for adjusting said link connectionso that the relationship betweenthe link and pressure plate is'changed but the same relationship is maintained between the linkand leverpand spring means acting to cause movement or" the pressure,

plate in one direction. g; Y

10. In a clutch comprising a driving element anda driven element, aback plate, apressure plate mounted to turn with the dri ing element and the back plate, and means for moving. the pressure plate relative to the plate COlC'i-1 prising a part projectingrearwardly from pressure plate, a lever pivotally mounted inte mediate its ends on a support projecting rearvqardly from the back plate and arranged: to have pivotal movement communicated thereto at its inner end, the outer end being'disposed for connection with the part reaching rearwardly from the pressure plate, an adjustable threaded connection directly between the lever and said part, the rotatable nut part of said connection being rigidly mounted on the lever and spring means acting normallyto move the-pressure platein one direction.

11.111 a friction clutch comprising a driving element, a driven element, a pressure plate for causing engagement between the driving and driven elements, and spring--n1eans acting to move the'pressure plate in one direction, means rfor manually moving the pressure plateconiprising a pivotally mounted release lever arranged to havepivotal movement communicated thereto to communicate movement to the pressure plate, a stud forconnecting the pressure plate to the lever for inovernentwith the latter, and a t'ion of said stud,

nut threaded on the stud and having a swivel" mounting on the lever so as to be turnable with respect to the lever whileheld. against axial movement relative-thereto, whereby, to" permit adjustment of the connection between the lever,

and pressure plate while maintaining the'same relation between the nut and-the lever.

, 12. In a clutch comprising a driving, element and a driven element, a back plate, .a pressure port projecting rearwardly from the back plate, said lever being arrangedv to have pivotal movement communicated thereto at-its inner end, and anadjustable link connection between the pressure plateand the outer end of said lever, said connection comprising a link pivotally' connected at one end with the outer end of the lever, a stud mounted at one end on the pressure plate'an'd having its other end threaded and reaching to the free end of the link, and a nutswiveled on the link and adjustably threaded on the threaded end of said stud.

13. In aclutch, the combination with a front driving member, of an assembly comprising a rear driving member arranged to turn with the frontdrivingmember, means for moving the driving members toward each other to engage a driven member therebetween, a stud extending rear-- wardly from the rear driving member and having. a threaded portion, a post rigid with the front driving member, a lever, pivoted on the post, and;

a nut swiveled on thelever-so' as to be freeito turn with respectto the lever while held againstaxial movement, with respect thereto, said nut; being adjustably threaded on WILLIAM n HUGHES. .l

the threaded por- V 

